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Commitments - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Mar. 31, 2025	Jun. 30, 2025	Dec. 31, 2024
Other Commitments [Line Items]
Threshold of outstanding principal balance on maximum claim amount (as a percent)		98.00%
Floating Rate Reverse Mortgage Loans
Other Commitments [Line Items]
Additional borrowing capacity to borrowers		$ 3,000.0	$ 3,100.0
Funded amount in connection with reverse mortgage loans		157.0
Forward Mortgage Loan Interest Rate Lock Commitments
Other Commitments [Line Items]
Short-term commitments to lend		2,000.0
Reverse loans IRLCs
Other Commitments [Line Items]
Short-term commitments to lend		$ 33.0
Rithm Capital Corp
Other Commitments [Line Items]
Mortgage Loans, Right To Transfer, Percentage		15.00%
Unpaid Principal Balance, Transfers Out	$ 5,700.0
Unpaid Principal Balance, Amount Expected to Deboard		$ 1,800.0
Customer Concentration Risk | Servicing And Subservicing Fees Benchmark | Rithm Capital Corp
Other Commitments [Line Items]
Concentration risk (percent)		13.00%
Concentration Risk, Amount		$ 41.6
Customer Concentration Risk | Unpaid Principal Balance | Rithm Capital Corp
Other Commitments [Line Items]
Concentration risk (percent)		11.00%
Concentration Risk, Amount		$ 33,800.0
Customer Concentration Risk | Loan Count | Rithm Capital Corp
Other Commitments [Line Items]
Concentration risk (percent)		20.00%
Customer Concentration Risk | Delinquent Loans | Rithm Capital Corp
Other Commitments [Line Items]
Concentration risk (percent)		59.00%
Customer Concentration Risk | Pledged MSR Liability Expense Benchmark | Rithm Capital Corp
Other Commitments [Line Items]
Concentration Risk, Amount		$ 18.6

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